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NASA Scientists working with the 230-foot-wide (70-meter) Deep Space Network antenna at Goldstone, Calif., have released a second, longer, and more refined, movie clip of asteroid 2005 YU55. The images were generated from data collected at Goldstone on Nov. 7, 2011, between 11:24 a.m. and 1:35 p.m. PST (2:24 p.m. and 4:35 p.m. EST).

Each of the 28 frames required 20 minutes of data collection by the Goldstone radar. At the time of the observations, 2005 YU55 was approximately 860,000 miles (1.4 million kilometers) from Earth. The resolution is about 13 feet (4 meters) per pixel. 2005 YU55 takes approximately 18 hours to complete one rotation, so the rotation in the movie appears much more rapid than the actual asteroid rotation speed.

The Goldstone observations utilized a new system to obtain images with a resolution of 4 meters, which is five times finer than the highest resolution previously possible at Goldstone.

As asteroid 2005 YU55 swept past Earth in the early morning hours of Wednesday, Nov. 9, telescopes aboard NASA’s Swift satellite joined professional and amateur astronomers around the globe in monitoring the fast-moving space rock. The unique ultraviolet data will aid scientists in understanding the asteroid’s surface composition.

“Swift’s ultraviolet and X-ray capability gives scientists a unique perspective on comets and asteroids, expanding the spectral window beyond the radio, infrared and optical observations so well handled by big ground-based facilities,” said Sergio Campana, a Swift team member at Brera Observatory in Merate, Italy. Campana requested that the spacecraft train its telescopes on the asteroid as a target of opportunity.

Although Swift is better known for its study of high-energy outbursts and cosmic explosions, the versatile satellite has made valuable observations of passing comets and asteroids as well. All told, the spacecraft has observed ten asteroids, including Vesta — now being studied close-up by NASA’s Dawn spacecraft — and Scheila, which brightened unexpectedly in late 2010 after colliding with a much smaller asteroid.

Scientists working with the 230-foot-wide (70-meter) Deep Space Network antenna at Goldstone, Calif., have generated a short movie clip of asteroid 2005 YU55. The images were generated from data collected at Goldstone on Nov. 7, 2011, between 11:24 a.m. and 1:35 p.m. PST (2:24 p.m. and 4:35 p.m. EST). They are the highest-resolution images ever generated by radar of a near-Earth object.

Each of the six frames required 20 minutes of data collection by the Goldstone radar. At the time, 2005 YU55 was approximately 860,000 miles (1.38 million kilometers) away from Earth. Resolution is 4 meters per pixel.
“The movie shows the small subset of images obtained at Goldstone on November 7 that have finished processing. By animating a sequence of radar images, we can see more surface detail than is visible otherwise,” said radar astronomer Lance Benner, the principal investigator for the 2005 YU55 observations, from NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The animation reveals a number of puzzling structures on the surface that we don’t yet understand. To date, we’ve seen less than one half of the surface, so we expect more surprises.”

Earth is about to be visited by the largest close-approaching asteroid on record. Known as 2005 YU55, it is about a quarter mile (400 m) across, round, and quite dark. When it comes closest to us, at 6:28 p.m. EST (23:28 Universal Time) on November 8th, it will be 198,000 miles (319,000 km) from Earth’s surface — closer than the Moon’s orbit. Professional astronomers around the world will closely follow the asteroid as it glides across the sky.

Weather permitting, backyard skywatchers also have a chance to spot this interloper. A few hours after passing closest to us, it will peak in brightness at magnitude 11.1, roughly 100 times fainter than the limit of human vision. “The good news,” says Alan MacRobert of Sky & Telescopemagazine, “is that you should be able to spot the asteroid with your telescope if it has an aperture of at least 6 to 8 inches.”

The asteroid will safely fly past our planet slightly closer than the moon’s orbit on Nov. 8. The last time a space rock this large came as close to Earth was in 1976, although astronomers did not know about the flyby at the time. The next known approach of an asteroid this size will be in 2028.

The image was taken on Nov. 7 at 11:45 a.m. PST (2:45 p.m. EST/1945 UTC), when the asteroid was approximately 860,000 miles (1.38 million kilometers) away from Earth. Tracking of the aircraft carrier-sized asteroid began at Goldstone at 9:30 a.m. PDT on Nov. 4 with the 230-foot-wide (70-meter) antenna and lasted about two hours, with an additional four hours of tracking planned each day from Nov. 6 – 10.

Radar observations from the Arecibo Planetary Radar Facility in Puerto Rico will begin Nov. 8, the same day the asteroid will make its closest approach to Earth at 3:28 p.m. PST (6:28 p.m. EST/1128 UTC).

NASA radars are monitoring 2005 YU55, an asteroid the size of an aircraft carrier, as it heads for a Nov. 8th flyby of the Earth-Moon system. There is no danger to our planet. At closest approach on Tuesday at 3:28 pm PST (23:28 UT), the 400m-wide space rock will be 324,600 kilometers away, about 85% the distance from Earth to the Moon.

Professional astronomers are eagerly anticipating the flyby as the asteroid presents an exceptionally strong radar target. Powerful transmitters at Goldstone and Arecibo will ping the space rock as it passes by, revealing the asteroid’s shape and texture in crisp detail, and pinpointing its orbit for future flyby calculations.

Earth is about to be visited by the largest close-approaching asteroid on record. Known as 2005 YU55, it is about a quarter mile (400 m) across, round, and quite dark. When it comes closest to us, at 6:28 p.m. EST (23:28 Universal Time) on November 8th, it will be 198,000 miles (319,000 km) from Earth’s surface — closer than the Moon’s orbit. Professional astronomers around the world will closely follow the asteroid as it glides across the sky.

Weather permitting, backyard skywatchers also have a chance to spot this interloper. A few hours after passing closest to us, it will peak in brightness at magnitude 11.1, roughly 100 times fainter than the limit of human vision. “The good news,” says Alan MacRobert of Sky & Telescopemagazine, “is that you should be able to spot the asteroid with your telescope if it has an aperture of at least 6 to 8 inches.”

NASA scientists will be tracking asteroid 2005 YU55 with antennas of the agency’s Deep Space Network at Goldstone, Calif., as the space rock safely flies past Earth slightly closer than the moon’s orbit on Nov. 8. Scientists are treating the flyby of the 1,300-foot-wide (400-meter) asteroid as a science target of opportunity – allowing instruments on “spacecraft Earth” to scan it during the close pass.

Tracking of the aircraft carrier-sized asteroid will begin at 9:30 a.m. local time (PDT) on Nov. 4, using the massive 70-meter (230-foot) Deep Space Network antenna, and last for about two hours. The asteroid will continue to be tracked by Goldstone for at least four hours each day from Nov. 6 through Nov. 10. Radar observations from the Arecibo Planetary Radar Facility in Puerto Rico will begin on Nov. 8, the same day the asteroid will make its closest approach to Earth at 3:28 p.m. PST.

The trajectory of asteroid 2005 YU55 is well understood. At the point of closest approach, it will be no closer than 201,700 miles (324,600 kilometers) or 0.85 the distance from the moon to Earth. The gravitational influence of the asteroid will have no detectable effect on anything here on Earth, including our planet’s tides or tectonic plates. Although 2005 YU55 is in an orbit that regularly brings it to the vicinity of Earth (and Venus and Mars), the 2011 encounter with Earth is the closest this space rock has come for at least the last 200 years.